The present invention relates to a golf club head having an improved weight means and, in particular to a metal wood type golf club head having an integrally formed weight structure within the club head cavity and adjacent the top surface thereof. Conventional wood type golf club designs are currently being replaced by metal wood golf club heads formed by a heavy duty metal shell with a hollow interior.
Although metal wood heads have been known for a number of years, as evidenced by the 1926 patent to Dunn U.S. Pat. No. 1,568,888, and the Australian patent to Cates 211781 of 1957, there have been a number of improvements in metal wood head construction as shown in the patent to Zebelean U.S. Pat. No. 4,432,549 and Kochevar U.S. Pat. No. 4,502,687, among others.
More recently, it has been found that moving the weight from the bottom surface of the club head toward the top surface creates a club with more favorable playing characteristics under a number of conditions. Placement of the weight near the upper portion of the club head increases stability of the club head as it is swung, and raises the center of percussion (CP) and/or center of gravity (CG) toward the upper surface of the club head which produces a truer flight path when a ball is properly struck.
The present invention is directed to a metal wood type golf club head having an internal weighting mass directly under and integrally formed with the upper surface of the club head. The weight mass extends in a longitudinal direction from a point adjacent the ball striking face to a second point adjacent the rear of the club head, and is centrally disposed relative to the ball striking face; that is it is above and beyond the center of percussion (CP) on the ball striking face. The mass is relatively wide and extends at least 0.5 inches up to approximately 1.5 inches the entire length of the club head in the front to rear direction.
Preferably, the thickness of the walls of the metal wood club head shell are in the order of 0.060 inches adjacent the top of the club head to a maximum of approximately 0.125 inches near the normally thicker sole. The present invention contemplates using a weighted mass having at least a thickness of 0.200 inches to a maximum of approximately 0.500 inches.
This structure provides a club head with significant upper weight which provides the various advantages described hereinabove. Various embodiments of the club head are contemplated using different size and shape internal weights. A further embodiment provides the exterior of the metal wood golf club head with an aerodynamic slot in the upper surface wherein the internal weight is formed on the underside of the slot within the cavity placing the weight even further toward the geometrical center of the interior of the club head.
Among the objects of the present invention are the provision of a metal wood type golf club head having improved internal weighting system wherein the weight is located adjacent the upper surface and within the metal shell of the club head in a longitudinal direction perpendicular to the ball striking face. These and other objects of the present invention will become apparent with the specification and drawings.